Hi, I could have posted this question in this category or in the Evolution or Zoology, but I think it has perhaps a bigger chance of getting an answer here.

So what I am looking for is to understand if there are any clear theories/explanations or evolutionary evidence on how come the: Eyes: visual senseNose: olfactoryEars: hearingVocal tract: food + speech

somehow all happened to evolve in a very small locality in the human body. Is this the case with all primates? or animals? to me it seems of course trivial to see the benefits of this, but I'm trying to somehow formulate it in a scientific text to show the importance of the human face for communication from an evolutionary perspective.

so more specific questions which possibly are somewhere on the web but couldn't really manage to get answers for:

-Is there a clear reason why the vocal tract is combined with the mouth, does this offer any survival advantage of is it perhaps just a energy optimisation?

- is there a reason why the mouth happens to be in between the ears ? is it the case in all vertebrates ?(this appears to be optimal for oral communication, because by talking to the sound source i.e. the other persons mouth, we are sending the signal in the optimal direction for him to hear i.e. in between the ears).